docstr: Returns whether a word is in the dictionary.
docstr_tok: ["Returns","whether","a","word","is","in","the","dictionary","."]
code: def __contains__(self, w):
      """
      Returns whether a word is in the dictionary.
      """
      return w in self.word2id
  
file_path: pytext/pytext/data/xlm_dictionary.py
imports: import os
  from logging import getLogger
  import numpy
  import torch
  from pytext.utils.file_io import PathManager
label_desc: Use image node_id 4 for calling the Dictionary obj's underlying member method code with example usage: obj.__contains__(w) and returns: unknown